Conventional overhead doors and sectional garage doors are heavy and rely upon counterbalancing mechanisms to provide for safe and easy manipulation. Various types of counterbalancing mechanisms are described and illustrated in "Homeowner's Garage Door Repair Manual" by Johnson and Davis, published 1980, SBN TXU 38-578.
One common means of counterbalancing overhead doors employs a torsion bar extending through coiled torsion springs and disposed horizontally above the door opening. An end cone and bracket generally anchor one end of the spring to the wall of the building and a winding cone adjustably secures the opposite end of the spring to the torsion bar. Pulley drums attached to the outer ends of the torsion bar receive cables secured to the lower end of the door. As the door is moved to the closed position, the pulley drums and torsion bar are rotated, winding or "loading" the torsion springs. This "loaded" spring force is imparted to the cables and provides a counterbalancing force which enhances the ease with which the otherwise very heavy door may be raised or lowered.
The proper balancing of an overhead door requires that, even when the door is in the open or raised position, the torsion springs be wound or "loaded" to a certain extent. Thus, the torsion springs will be "loaded" at all times.
Metal fatigue may cause torsion springs to break. Conventional methods of repairing a torsion spring counterbalance requires disassembly of the mechanism and immediate replacement of the torsion spring. However, replacement torsion springs are not always immediately available. Additionally, failure of a torsion counterbalance may result in a family car or emergency vehicle being "trapped" inside a garage behind a heavy and virtually immovable door. A method of at least temporarily repairing a broken torsion spring would allow manipulation of the door until replacement springs can be acquired and permanently repaired.
It is an object of the present invention to eliminate the need to disassemble the mechanism and also to eliminate the necessity of immediately replacing a broken torsion spring.
Accordingly, it is a primary aim of the present invention to provide a method and apparatus for repairing broken torsion springs without removing broken torsion springs from the torsion bar. Other objects and advantages of the present invention will be apparent upon reading the following detailed description.